Substance for treating hides and process of making same.



SUBSTANCE FOR TRBATI APPLICATION FILED SEPT. 16, 1906.

1 o. H. NOWAK. NG run s AND PROCESS o PATENTED DEC. 10, 1907.

FMAKING SAME.

uNrTEn sTArEs PATENT oFFlroE.

.orroKAn HENRY NOWAK, OF CHICAGO, ILLINOIS, ASSIGNOR TO NOWAKMANUFACTURING COMPANY, A CORPORATION OF ILLINOIS.

SUBSTANCE FOR TREATING HIDES AND- PROCESS OF MAKING SAME.

To all-whom it may concern! Be it known that I, O'r'roKAR" HENRY NowAK,a subject of the Emperor of Austria- Hungary, residing at Chicago,county of Cook, State of Illinois, have invented a certain new anduseful Improvement in' Substances for Treating Hides and Processes ofMaking the Same, and declare the following -to be a full, clear, and.exact description of the same, such as will enable others skilled in theart to which it pertains tomake anduse the same, reference being had tothe accompanying drawings, which form a part of this specification.

My invention relates to a substance for use in preparing and tanninghides and skins,

. hides or skins.

and tea process of from milk.

In the practice of the so-called uic tanning processes'to convert the hies -or.

skins into leather, sulfuric or other mineral acid is often used inbatingor unliming, in plumping or swelling, and. in composition withtannic' acid in tanning. The mineral acids employed in such quickprocesses renvder the leather hard-and brittle and con-1sequentlydeteriorate its quality.v The acids also deleteriously affectthe gelatin in the hides and skins to'such an extent that it is a commonpractice to treat them with glucose to increase their Weight.

, In order that the highest possible grade of leathermay be made,substances should be used in the several steps of the tanning processwhich are: 1. Free from all mineral they will be readily impregnatedwith the .will possessthe above enumerated desirabletannage, and capableof depleting the-hides or "skins in making the lighter classes ofleather to leave them thin and flexible.

The primary object of my invention is to provide a substance for use Intanning which characteristics.

My invention as herein disclosed may be u Specification of LettersPatent.

Applic i n l September 16. 1905. Serial No. 2781822.

producing such substance I process.

4'. Incapable duce asses of leather so that Patented Dec. 10,1907.

generally described .as'a process consisting in precipitating the curdin milk, removing the" precipitated curd, changing the con-- dition ofthesour liquor remaining after the removal of the curd by permittingfermentation thereof for a period of at least seven days, so that itcontains at least 1% acidity calculated as lactic acid, concentratingthe fermented sour liquor, and finally adding some unconcentr'atedfermented sour liquor to the concentrated fermented sour liquor.

My invention also consists in a' bacterial substance derived from milkcomposed of concentrated and unconcentrated fermented sour liquor.

My invention will be more fully described hereinafter with reference tothe accompanying drawing in which is illustrated one form of apparatusfor practicing my improducing my 1m proved process and for provedproduct.

My invention consists essentially inpreparing from cows'milk, either inthe form of skimmed milk or buttermilk, a'substance to ,be used inseveral of the steps of the tanning The average cows milk contains atleast 2.5. grams ofcitric acid in every1000 grams, which renders milk ofreat value as a substance for use in tanning eather owing to citric acidpossessing the above enumerated desired characteristics.

permit. the precipitation of the curd containe in skimmed milk, or inbuttermilk, or in a mixture of skimmed milk and Y buttermilk,whichfgenerally occursas the result of decomposition within twelve hoursfrom the time of the removal of the cream, at a temperature of 120130125 degrees F. The preci itation is effected by the'sourness probythe decomposition of the milk rather than by the usual practice ofusingsulfuric, hydro-.chloric, er acetic acid, or rennet, in order that theproduct derived from the milk may have only-natural organic acidity andbe entirely free from foreign acids or substances? The precipitatedcurdis next removed from the. liquid part of the milk in any desiredmanner, as by use of a mechanical separator. In order to promotetheprecipit'ation' of the curd a redetermined quantity of the naturalsour 'quor previously obtained from milk after removing the curdtherefrom, is added while the milk is constantlyagitated. When the milkhas been placed 1n a tank of 2500 gallons capacity containing 1900 to2000 gallons of" 1 milk after removing the curd therefrom, is

sufficient.

- The sour liquor-remaining after the removal of the curd is placed in awooden vat or tank, a series of such vats being provided so that theliquor produced each day may be placed in a separate vat, and.allow'edto remain there a predetermined period of time, preferably twelve daysWhile fermentation is taking place. In addition to the natural acidityof about 1.5% calculated as lactic acid, the sour liquor contains sugarof milk asits principal component which is converted into acids byfermentation. In order to start the fermentation more quickly andthoroughly, and to increase the same, sour rye flour dough is added toeach vat or tank, which acts similarly to yeast. Fourounces of the sourdough added to each 2500 gallons is sufficient. The use of sour doughis, however, not essential as the continuous use of vats orv tanksresults in bacteria being present in the wood in sufficient quantity toproduce the fermentation without adding any ingredient such as sourdough. The sour liquor increases its temperature to about 90 to 1m)degrees F. on the third day, when life or action commences resulting inthe generation of carbonic acid gas by the fermentation and oxidation ofthe sugar of milk as it is converted into acid. This action continues,the fermentation and oxidation increasing from day to day with a slightincrease of temperature, until about the seventh day when thefermentation slows d wn rapidly and finally ceases. This pe 'riod offermentation results in an increase of acidity to from 3.5% to 4%. Thefermented sour liquor. thus obtained'may be,

used in the various steps of the tanning process in lieu of the sulfuricor other acid at present usually employed, but in order that the storageand transportation of the sour liquor to the tanneries may befacilitated, it

is preferably concentrated to a'consistencysimilar to that of condensedmilk, or that of paste, or even, if desired, it may be converted into adry, solid, extract of crystal-like form.

In the drawing is illustrated a convenient form of apparatus forconcentrating the sour liquor.

' Reference characters A A A A, A, A, A A indicate wooden vats or tankseach of which contains the sour liquor. The vats may be supported in anysuitable manner,

asfor instance by astructure A. Depending.

within the vats are pipes BQB, B B B B B", B, the lower ends of whichare open and are located adjacent to the bottoms of the vats. The upperends of the pipes are connected to a common conduit B whichcornmunicates-with vacuum pan C. A valve 1) controls the communicationfrom each of the pipes Within the several vats and the pipe B, while avalve 1) controls the communication of the common pipe B with the vaeeumpan. The vacuum pan has a series of tubes C connected at their oppositeends with headers 0 Steam is admitted to the space supply conduit H.

H indicates the conduit through which the steam passes from the spacearound the vertical tubes. -A dischargepip'e E lea ls from the bottom Cof the vacuum pan through which the condensedliquor is per mitted toflow .by opening a valve 6 into a suitable receptacle F.

D indicates a conduit extending from the interior of the vacuum pan nearthe top thereof from which vapor is exhausted by any suitable means. Inorder that the condition of the liquor within the vacuum pan may beascertained a gage G is provided the ends of which communicate with theinterior of the vacuum pan. Valves g and 9 control the communicationbetween the ends of the gage and the vacuum panwhile a valve-g controlsthe discharge of the liquor from the a e. g The tank in which the sourliquor has completedfermentation is connected with the vacuum pan byopening the valve 1) while the corresponding valvesof the other vatsremain closed. The exhaust mechanism withdraws the vapor through thepipe D and thereby causes the liquor from the vat to be drawn into thevacuum pan.. The liquor passes'through the vertical tubes C and isheated to the desired degree by the steam surrounding such tubes. Theevaporation continues until the desired concentration ,has beenaccomplished. When the concentrated liquor is to have the consistency ofcondensed milk, six pounds of the sour liquor from the vat are reducedto one pound ofabout 1.8"t0 24% acidity andhaving a specific gravity of1.116 or 15 degrees Baum at a temperature of 60 degrees F. The exactconsistency of the liquorwithin the vacuum pan may be readilyascertained by opening the valves 9' and g to permit the liquor to flowintothe gage Grand then closing such valves and opening the valve g. I I

The consistency of liquor is indicated by its appearance within the gageas it is a clear green at first and subsequently becomes so sticky as toadhere to the interior of the glass gage. When the desired consistencyhas been attained the condensed liquor is permitted to flow through theconduit E from the vacuum pan in the receptacle F.

In order that the concentrated liquor may possess the desired bacterialaction, from'one to five gallons of the unconcentrated natural sourliquor are added and thoroughlymixed with fifty gallons of theconcentrated liquor -having mixed therewith unconcentrated liquor.

From the foregoing description it will be observed that I have inventeda bacterial substance, and a process for making the same from milk, ofhigh natural organic acidity containing no foreign substances whatever,and read ly miscible in even cold water,

thereby rendering it possible to make the substance of any desired liuid form and strength. Whilemyimprover substance conwill accomplishthedesired result.

tains about 18 to 24% free organic acidity, and, about 14 to 16%anhydrous organic acidity, such as-citric acid, lactic acid, sugar ofmilk and some -albumenoids,.it contains'no mineral or other acid, orother-ingredient which would in any way injure'the texture of the skinsor hides or attack the gelatin therein. a

My improved bacterial substance may be utilized in various waysintanning leather and may be readily adapted to difierent processes oftreating hides and skins in the manufacture of all kinds of leather, andI there- 'fore do not wish to limit myself to any particular proportionsof the substance to be used in the various steps of tanning processes. Ihave, however, found in practice that in bating or unliming one poundconcentrated, or six pounds of raw liquor is sufficient for 100 poundsof raw hides or skins. Even larger quantities will, however, have noinjurious effect and smaller quantities In the step of pickling orpreserving approximately one half pound of concentrated or three poundsof the raw fermented liquor may be used for 100 ounds of raw hides orskins in connection with the required amount of salt. For plumping orswelling 100 pounds of hides or skins three pounds of the-concentratedadded to 800 gallons of water or 18. pounds of the unooncentrated liquorwithout any water, may be successfully used and even a bath of theconcentrated liquor alone will not injure hides but will accomplish theplumping rapidly. In the tanning or filling step an addition threepounds of concentrated' or 18 pounds of unconcentrated liquor to thetanmc liquor is sufficient for the re. quired fermentation, but; agreater or less quantity may-be used with excellent'results 'When it isdesired to plump skins or hides they are treated in cold water to' whichhas been added my improved substance and the treatment is contmued for aconsiderable period in order to enable the bacteria to develop and actupon the organic matters of the hides or skins'.- After the plumpingprocess has been completed the hides or skms.

are found to be heavier and at the sametime of -finer texture thanbefore treatment. In making the lighter classes of leather the only stepof the process in which it isdesirable to use my improved fermentedsubstance is that of bating. The treatment for this purpose isaccomplished at a temperature of to degrees F., but it is continned foronly a short time so that the badteria are not given an opportunity todevelop; the hides-0r skins are therefore depleted, that is, renderedthin and flexible to such an extent that the pressure Ofjlle fingersupon the hides or skins leaves substantially transparent marks. f

Having now fully described my invention, what Iclaim as new and desireto secure by Letters Patent is 1. The process of making. a substance forthe purpose described which consists in removing the curd from milk andin permitting the sour liquor remaining after the removal of the curd toferment for a period of at least seven days.

2. The process of making a substance for the purpose. described whichconsists in heating milk to promote the precipitation of the curd, inremoving the precipitated curd, and in permitting the sour liquorremaining after the removal of the curd to ferment for a period of atleast seven days.

3. The process of making a substance for the purpose described,. whichconsists in heating milk to promote the precipitation of the curd,further promoting the precipitation' by adding sour. liquor previouslyobtained from'milk, removing the precipitated curd, and, permitting thesour liquor re.- maining after the removal of the curd to ferment for asufficient period to convert at least 1% thereof into acid. I

4. The process of making a substance for the purpose describedwhichrconsists in re moving the'curd from milk, and in permitting the.sour liquor remaining after the removal' of the curd to ferment for asuflicient period to. convert at least 1% thereof into acid calculatedas lactic acid.

5. The process of making a substance for the purpose described, whichconsists in promoting the precipitation of the curd in milk by addingthereto sour liquor previously obtained from milk, in removing theprecipitated curd, and in permitting the sour liquor remaining after theremoval of the curd to ferment fora sufficient period to develop atleast 1% acidity calculated as lactic acid.

ithe" purpose described which consists in removing the curd from milk,in developing bacteria in. the sour liquor remaining after the removalof the curd by permitting fermentation thereof for a su'llicient periodto convert at least 1% thereof into acid calculated as lactic acid, andin concentrating the fermented sour liquor to a degree insufficient todestroy the developed bacteria.

7. The process of making a substance for the purpose described, whichconsists in removing the curd from milk, permitting the sour liquorremaining after removing the curd to ferment for a suflicient period toconvert at least 1% thereof into acid calculated aslactic acid, inconcentrating the fermented sour liquor, and in adding a predeterminedquantity of unconcentrated fermented sour liquor obtained from milk.

. 8. The process of making a substance for the purpose described, whichconsists in removing the eurd from milkjpermitting the sour liquor afterthe removal of the curd to ferment for a suflicient period to convert atleast 1% thereof into acid -calculated as lacticacid, promotingfermentation by adthe fermented sour liquor.

9. A bacterial substance for the purpose described, produced from Wheyand composed of fermented sour liquor having at least 1% aciditycalculated as lactic acid.

10. A bacterial substance for the purpose described, produced from wheyand c0n1- posed of concentrated fermented sour liquor having at least 1%acidity calculated as lactic acid before concentration.

11. A bacterial substance for the purpose described, produced from wheyand composed of concentrated fermented sour liquor having at leastacidity calculated as lactic acid, and uneoneentrated fermented sourliquor having at least 1% acidity calculatedas lactic acid. i

In testimony whereof, I sign this specification in the presence of twoWitnesses.

OTTOKAR HENRY NOWAK.

Witnesses:

GEO. L. WILKINSON, O. A. MULLEN.

ding sour. ryel'lo'ur dougln'and concentrating

